Thanan Bestiary: Bruma

The bruma is a tyrannosaurid that is highly adapted for arctic environments, and is the apex predator of the northern-most parts of the globe. They fill the same niche polar bears do in the modern era.

Appearance: Bruma are a species of tyrannosaudid that grow to about 3m long, not including the tail, and almost 2m high. They are distinctly stocky compared to other tyrannosaurs with shorter, fatter tails and bulky torsos. Their entire bodies excluding the toe pads are thickly covered with feathers. The outer layer is closely fitting and waterproof and pure white in adults; immature bruma have mottled patches of pale grey along their dorsal region. Beneath is a thick layer of fluffy down that traps air to insulate the bruma against the cold, and doubles as a buoyancy aid when swimming. Bruma hold their heads close to their body when at rest, making them appear to have abnormally short necks. Their small forearms tucked against their chest and extremely difficult to see, leading to the common myth that bruma have no arms at all. Unlike many therapods, male and female bruma are the same size.

Behaviour: Bruma prefer to attack from ambush, hitting with a powerful bite and using it to grapple their prey and drag it out of the water before clawing or pinning with their feet and tearing with their jaws. Land-based prey may be chased for short distances but bruma do not have the speed to run down fast prey. Instead they target creatures sheltering in burrows or hiding beneath snow. Bruma are solitary hunters who roam over large distances and do not protect individual territories, but will chase away other bruma if encountered outside breeding season.

Breeding occurs in summer when the melting ice forces individuals together. Females retain sperm throughout autumn within specialised parts of their reproductive trait and use it to fertilise eggs the next winter. Two eggs are laid in early summer and brooded by the female. The hatchlings are cared for until late in the next spring.